Cost Optimization Gone Wrong: Lessons from Using Arm Runners in GitHub Actions for Fargate Spot

Cost Optimization Gone Wrong: Lessons from Using Arm Runners in GitHub Actions for Fargate Spot

About six months ago, I wrote an article about how to cut costs using Fargate and Fargate Spot. At the time, I kept the GitHub Actions runner as the default x86 architecture (ubuntu-latest) and introduced a method to support ARM builds using QEMU-based cross-compilation. However, once I put it into production, I faced a major issue: build times were noticeably longer—by several minutes. As a result, I gave up on ARM builds for the time being. Ma…